1. Industrial Field of the Invention
The present invention relates to a magnetic recording/playback apparatus, and more particularly, to a loading mechanism which can realize reduction of the size, weight and thickness of such an apparatus.
2. Description of the Prior Art
Recently, various kinds of trials have been made for reducing the size, weight and thickness of a magnetic recording/playback apparatus, especially, a video-camera integrated magnetic recording/playback apparatus. Among others, a number of loading mechanisms in the apparatus have been subjected and practically developed.
A conventional loading mechanism will be described hereinafter with reference to the drawings (FIGS. 15 and 16).
Generally, in the conventional loading mechanism which withdraws a magnetic tape from a tape cassette so as to wind it around the outer periphery of a rotary head cylinder, there are provided one or more fixture posts between a position where the tape leaves out of the rotary head cylinder and a capstan, for forming a running path of the tape.
More specifically, as shown in FIG. 15, the loading mechanism includes first, second and third loading roller posts 91, 92 and 93 which withdraw a magnetic tape 94 from a tape cassette 95 and wind the same around a rotary head cylinder 96. The tape 94 inclinedly leaves from the cylinder 96 by means of the second roller post 92. Then, the tape 94 passes the first roller post 91 and arrives at a inclined fixed post 97 and torsion of the tape 94 is modified by the post 97 so that the inclined path of the tape is converted into a normal horizontally-running path. Thereafter, the running path of the tape is guided for extending to arrive at a capstan 100 through an audio control head 98 and a fixed post 99 (see JP-A-3-127372).
However, in the above-described structure, since two fixed posts, that is, the inclined post 97 and the post 99 are provided in a pathway extending from the position where the tape leaves out of the cylinder 96 to the capstan 100, the tape running load caused by the two fixed posts is increased largely and a tape tension before reaching to the capstan is also increased. As a result, it is impossible to reduce the capstan in size and weight, and further a tape damage is liable to occur.
This is because component parts of the fixed posts for guiding the tape are fixed stationarily with respect to a chassis so that the frictional force between the tape and the fixed posts becomes large, which affects the tape tension to a considerable degree, while the roller posts can guide the magnetic tape smoothly due to rotation of rollers of the posts for guiding the tape.
Further, it is common in the conventional loading mechanism that loading boats (or loading movable carriers) provided with the loading posts are connected to loading rings via relay linkages, for the purpose of moving the loading boats desirably.
More specifically, in the loading device as shown in FIG. 16, a supply side ring gear 101 and a take-up side ring gear 102 each having substantially the same dimensions, are vertically superposed substantially concentrically, in order to guide a supply side boat 104 with a supply loading post 103 along a loading guide 107 and to guide a take-up side boat 106 with a take-up loading post 105 along a loading guide groove 108; the ring gear 101 is connected to the boat 104 via a relay linkage 109 and the ring gear 102 is connected to the boat 106 via a relay linkage 110, in accordance with pathways of movements of the boats 104 and 106.
However, because the relay linkages are always required in such conventional structure and the number of component parts is accordingly increased, there occurs a trouble in improving an assembling efficiency of the apparatus and reducing the size, weight and thickness of the apparatus.